Abstract: A probe tip structure is disclosed which is obtained from a solid piece of material having a bore machined therein which extends from a first end where the probe tip is attached to a coaxial transmission line to a second end where contact points are machined therein. The inner conductor of the transmission line extends into the bore to the second end of the probe tip where another contact point is formed. All contact points are adapted to contact a device under test. A rigid insulating structure is placed within the bore of the probe tip to hold the inner conductor securely in a fixed position.

Abstract: This invention involves a memory cell of, for example, the metal-oxide-semiconductor (MOS) capacitor type, which is accessed for reading and writing by means of an access network connected to the memory cell through a gating transistor, and which is provided with an independent refresh network for maintaining the memory state of the cell in the absence of an access writing signal. The refresh network includes a pair of IGFET (Insulated Gate Field-Effect Transistors) transistors connected between the MOS capacitor and an AC refresh line which is completely independent of the electrical access network. Either a "full" or "empty" capacitor memory state, binary digital 1 or 0, respectively, is maintained without the need for interrupting the reading and writing of the MOS capacitor through the gating transistor.